Modulator processing for a parametric speaker system
US7162042B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 21, 2003 |
| Grant date | Jan 9, 2007 |
| Priority date | — |
| Expiry date | Mar 21, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R2217/03
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A parametric loudspeaker system using improved modulators to compensate for the non-linearity of the parametric process in air when driving the air at saturation levels and below saturation levels. The parametric loudspeaker uses a pre-processed single sideband modulator that offers ideal linearity as characterized by square root pre-processed double sideband modulators but with a lower carrier frequency and without the wide bandwidth requirements. By eliminating some or all of the lower sideband the carrier frequency can be reduced without producing sideband frequencies in the audible range. Lower operational frequencies result in greater translation efficiency and greater output capability before reaching the saturation limit of air. A pre-processor minimizes the effects of saturation limits for double sideband, truncated double sideband or single sideband processing to achieve superior output.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.